Conventionally, gamma correction that corrects a gamma characteristic of a monitor by inputting image data having a reverse characteristic to a characteristic of the monitor is known. For example, Non-Patent Document 1 describes transmission of a video stream obtained by encoding transmission image data obtained by applying photo-electric conversion to high-dynamic-range (HDR) image data having a level range of 0 to 100% N (N is larger than 1).
Conventional low-dynamic-range (LDR) imaue is operated by mainly referring to brightness (a brightness level) of 100 cd/m**2, adjusting a contrast ratio to the brightness to become 100:1, and using minimum brightness as a black level, based on defined photo-electric/electric-photo conversion characteristics. A HDR image has fine levels at the black side, and is required to have the brightness level expand and be displayed. At the time of a camera output, special photo-electric conversion for HDR is sometimes used.